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Posted By: LRA new old amp! :) urgent!! - 03/16/09 04:17 PM


I currently have a pio vsx-1018 AVR with an axiom 5.1 setup. I currently have m22ti for my fronts but I'm planning to buy the m80 full towers.

I was shopping for an amplifier to drive my new front.

[URL="http://www.usersmanualguide.com/yamaha_audio/integrated_amplifiers/ax-930"]yamaha ax-930 manual[/URL]



would that be a nice amp or should I try to get something else. I don't want to break my piggy or should I?

I can get it for 200$ CDN, it's a 91-92 amp..

worth it?

thanks
Posted By: LRA Re: new old amp! :) urgent!! - 03/16/09 04:41 PM
I also have two unused yamaha AVR and would it make sense to use one as a dedicated amp for my front?
Posted By: tomtuttle Re: new old amp! :) urgent!! - 03/16/09 04:57 PM
Luc, my opinion is that you should first try just the 1018 with the M80's to see if there is anything you don't like.

Then, if you decide you REALLY want to try using an external amp, I would not mess with older integrated amps or older AVR's. There is too much to go wrong over time with all the switches. And it is questionable to me that you would notice improvement over the amp section in your 1018.

For that much money, I would try to find either a decent used, dedicated power amp or a Refurb Onkyo M-282 at clubonkyo for $159US.
Posted By: SirQuack Re: new old amp! :) urgent!! - 03/16/09 05:09 PM
I agree, at 130w per channel, it is unlikely you will need a seperate amp. How loud do you listen and how big is your room?
Posted By: LRA Re: new old amp! :) urgent!! - 03/16/09 05:12 PM
 Originally Posted By: tomtuttle
Luc, my opinion is that you should first try just the 1018 with the M80's to see if there is anything you don't like.

Then, if you decide you REALLY want to try using an external amp, I would not mess with older integrated amps or older AVR's. There is too much to go wrong over time with all the switches. And it is questionable to me that you would notice improvement over the amp section in your 1018.

For that much money, I would try to find either a decent used, dedicated power amp or a Refurb Onkyo M-282 at clubonkyo for $159US.



from my pio's manual :

 Quote:
You can use speakers
with a nominal impedance between 6 Ω and 16 Ω (please see Switching the speaker impedance on page 74 if you plan
to use speakers with an impedance of less than 8 Ω).


There is a switch to select one or the other but nothing for 4ohm? will it still work well?

I'm really not experienced with this (or anything else! :-)
Posted By: LRA Re: new old amp! :) urgent!! - 03/16/09 05:13 PM
 Originally Posted By: sirquack
I agree, at 130w per channel, it is unlikely you will need a seperate amp. How loud do you listen and how big is your room?


I'm usually not going louder than -15db with my current setup (2xm22ti+2xqs8+vp100+12" psb sub)

room is around 14x15
Posted By: SirQuack Re: new old amp! :) urgent!! - 03/16/09 05:23 PM
I would try it first to see if you have issues, they you can look into getting additional power. I would leave the switch in the 8ohm position so you don't limit current to the speakers. The 80's are more efficient, so it should work. Worse thing that could happen is that you may have to get some amps later..
Posted By: davekro Separate amp for fronts - 03/16/09 05:45 PM
Can you guys explain why people add a separate amp for the fronts with say a 2809, 3808 or other similar quality of amps? Is it just for more power in the stereo music listening mode? When using in HT mode, it seem the fronts are not asked to do much, compared to the center, so would have much more headroom than would normally be needed in HT mode. What am I missing here?
Posted By: terzaghi Re: Separate amp for fronts - 03/16/09 06:17 PM
I think my fronts get far more of a workout than my center channel during most movies... unless it is one of those boring movies with nothing but dialogue and no action!

That being said... I use the 3808 to drive all of my speakers. I would like to add the axiom 2 channel amp for the fronts for stereo use. Too pricey for me though.
Posted By: SirQuack Re: Separate amp for fronts - 03/16/09 07:14 PM
Dave, I think for the most part it is for more clean, undistorted sound at higher listening levels. Most people have smaller rooms and probably don't make use of that extra "headroom". In my case I do have a much larger room and do have monoblocks for my m80's. However, my Denon 2805 alone does an admirable job.

Whenever I get a new receiver with Audyssey or Trinnov, I may sell my amps. I need cash$$$ \:\)
Posted By: jakewash Re: Separate amp for fronts - 03/16/09 07:17 PM
 Originally Posted By: davekro
Can you guys explain why people add a separate amp for the fronts with say a 2809, 3808 or other similar quality of amps? Is it just for more power in the stereo music listening mode? When using in HT mode, it seem the fronts are not asked to do much, compared to the center, so would have much more headroom than would normally be needed in HT mode. What am I missing here?
Because they want to, have spare money to burn and feel they are missing something with just their avr. ;\)

Many actually need the amp because they have unusually large rooms or listen at insanely loud volumes in which case they can benefit from the extra power. There are those that say they can hear better dynamics when using seperate amps. I hope to find out for myself someday.
Posted By: bridgman Re: Separate amp for fronts - 03/16/09 07:57 PM
Even in cases where the center channel carries as much or more signal than the mains, offloading the mains still frees up some power supply capacity for the center channel. It's like the difference between "one channel driven" and "all channels driven" power ratings.

This won't help in cases where there isn't enough "one channel driven" power for the center channel to keep up, but in cases where there is lots of power going into both mains and center (ie when the power supply voltage in the receiver is likely to droop under load) offloading the mains can make a difference.

The point about having bottomless power for music reproduction is also valid.

Finally, stereo amps often have nice analog power meters, which IMO always improve the perceived sound quality
Posted By: davekro Re: Separate amp for fronts - 03/16/09 08:49 PM
 Originally Posted By: bridgman
Even in cases where the center channel carries as much or more signal than the mains, offloading the mains still frees up some power supply capacity for the center channel. It's like the difference between "one channel driven" and "all channels driven" power ratings.

This won't help in cases where there isn't enough "one channel driven" power for the center channel to keep up, but in cases where there is lots of power going into both mains and center (ie when the power supply voltage in the receiver is likely to droop under load) off loading the mains can make a difference.

The point about having bottomless power for music reproduction is also valid.

Finally, stereo amps often have nice analog power meters, which IMO always improve the perceived sound quality



I was just going to ask about the lighter load on the PS. Glad you confirmed that thought. All the above makes sense now. Makes me lean harder towards the 3808 with a slight edge over the 2809 in power and with a larger power supply I am sure, as it weighs 11 lbs (39%) more. Then I f I feel the need to unweight the fronts from the 3808, I'll feel the surrounds will have plenty of power (maybe I am not as power hungry as some). \:D

I have read it here (JD? JohnK?) that if you bother to add an amp, it should be double the AVR's rated power. Is this just a common sense thought of not to bother with the expense for just an incremental increase, or is there more to it? This is just to edumacate myself. I don't see the need for my situation. But hey, when the term discretionary income comes back into my vocabulary, nice to have options. I am trusting we are under 'forum/ client privilege'. None of this gets back to the wife!
\:D
Posted By: jakewash Re: Separate amp for fronts - 03/16/09 09:15 PM
To audibly hear a difference the power needs to double, so if you get the 3808, you will need an amp that is capable of 260W/ch to get a noticably louder system, not that you might not hear it cleaner at high SPL for the same amount of power, say an amp with 150W, since it appears outboard amps tend to have a little more headroom built in(lower specs than actual output).
Posted By: davekro Re: Separate amp for fronts - 03/16/09 09:40 PM
 Originally Posted By: jakewash
To audibly hear a difference the power needs to double, so if you get the 3808, you will need an amp that is capable of 260W/ch to get a noticably louder system, not that you might not hear it cleaner at high SPL for the same amount of power, say an amp with 150W, since it appears outboard amps tend to have a little more headroom built in(lower specs than actual output).


Oh, that makes sense. I recall now the rule of thumb that you need to double the power to get a 3dB SPL increase. 3dB being what it takes for the average listener to notice the difference.

(Hey, JD over on the AVS thread, your repetition of this concept to me is FINALLY sinking in.) ;\)
Posted By: Wid Re: Separate amp for fronts - 03/16/09 09:43 PM
The 260 is assuming the speaker is an 8ohm speaker. Even more if your talking 4 ohm seeing the 3803 should put out around 200 watts into 4 ohm.
Posted By: davekro Re: Separate amp for fronts - 03/16/09 09:50 PM
Rick,
Well now you are compicatin' stuff. ;\)
If I ever do think to add an amp, I CAN remember to come back here and ask for a rec. \:\)
Posted By: ClubNeon Re: Separate amp for fronts - 03/16/09 09:52 PM
But a separate rated at 260 into 8 Ohms is also more than likely to gain around 50% more power into 4.
Posted By: Wid Re: Separate amp for fronts - 03/16/09 10:04 PM
The point being with a 4 ohm load you would need at least a 400 watt into 4 ohm amp for any real gain. A 260 watt amp is not quite going to get ya there even if you get the 50% increase....... real close though .
Posted By: davekro Re: Separate amp for fronts - 03/16/09 10:22 PM
Boy are you splitting watts there Rick, or watt. Can't ya give a guy a dime's worth of watts? ;\)
Posted By: Wid Re: Separate amp for fronts - 03/16/09 10:25 PM

Actually in my first post I had a brain fart and Chris is correct.
Posted By: tomtuttle Re: Separate amp for fronts - 03/16/09 11:22 PM
 Quote:
forum/ client privilege


I like that a lot!
Posted By: jakewash Re: Separate amp for fronts - 03/17/09 09:48 AM
I just doubled the 8Ohm usual spec that is the easiest to find when reading through spec sheets.

The 3808 is capable of 238W into 4 ohms according to some lab tests. So you would need a ~500W 4ohm capable amp to derive easily heard/loud benefits. This is where the Emotiva amps come into play, as they are the lowest priced amp, it seems, with these kind of specs avaialble.
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